Blount's disease is a progressive disease that affects the varus angle of the tibia in children that is correctable with proper treatment. This disease is a progressive developmental condition that is characterized by disordered endochondral ossification of the medial tibial physis. This results in an abrupt varus deformity in the proximal tibia and is also associated with an internal torsion of the tibia. Current treatment of Blount's disease includes use of static orthotic devices or surgical procedure also known as tibial osteotomy. These procedures can create other misalignments, are incremental, and unnecessarily slow.
There are two forms of Blount's disease recognized. First is an infantile form of the disease which occurs prior to three years of age. Second is an adolescent form which occurs after age eight. Diagnostic characteristics of Blount's disease consist of: sharp varus angulations in the metaphysis, a widened and irregular physeal line medially, a medially sloped and irregularly ossified epiphysis, and a prominent beaking of the medial metaphysis, with lucent cartilage islands in the beak. Additional symptoms include pain, progressive bowing, an abnormal gait, and leg length discrepancies. The cause of Blount's disease is currently unknown.
The nature of Blount's Disease is in the bowing of the tibial portion of the leg and is based on the diminished growth capacity of the medial area of the tibia and a continued normal growth emanating from the lateral area of the tibia. This condition results in the normal growth of the lateral portion of the tibia, while growth of the medial portion of the tibial shaft is suppressed. The abnormality exists due to the continued growth of the lateral epiphysis and the stunted growth of the medial epiphysis causing a curving of the leg. This causes the outward bowing of the tibia which usually occurs in infants and is most prominent just after they start walking.
Currently, the disease is treatable by application of conventional braces with limited success and an unnecessarily long treatment period. The known prior art devices utilized for the correction of the tibia are very restrictive in nature and are typically utilized when the leg of a patient is in a straight position. The conventional medical devices utilized for treatment of Blount's disease are based on the application of a three point pressure system. The typical application of the three point pressure system is as follows: (1) the proximal most portion of the brace is adapted to produce a counter force at the upper portion of the inner femur; (2) the most distal portion of the brace generates a counter force at the ankle; and (3) the corrective pressure is exerted by pressure from the lateral side towards the medial counter forces. Unfortunately, during application of the three point pressure system, deformation and correction occurs not only at the tibia, which needs to be corrected, but the compensatory deformation and correction of the bone structure also occurs at the femur, which does not need to be corrected. During this prior art procedure often a perfectly normal and healthy bone is involved in the corrective process by introducing forces that are typically unnecessarily adapted to bend and deform the femur. Review of the mechanics of Blount's disease conducted by the prior art devices leads to the conclusion that correction of the affected part, namely the tibia, is the primary concern in the treatment of patients and not the treatment of the femur. This is because the treatment of the femur introduces additional and undesired deformity to the child's limb.
Since it is known that Blount's disease occurs typically with weight-bearing, bracing devices and methods adapted for treatment of this disease should be effective throughout all phases of the patient's activity. To minimize the progression of Blount's disease, the epiphyseal plate of the tibia needs to be aligned correctly while ambulating. Then the tibia will correct itself, as shown in the prior art study.
Thus, there has been a long felt and unsolved need for a medical device and procedure adapted for treatment of Blount's disease and capable of overcoming the shortcomings of the prior art. Specifically, there has been a need for a medical device which is capable of isolating the corrective forces and directing them for treatment of the distal portion of the leg or treating the tibial bone without affecting the Femur bone or stretching the medial collateral ligament (which is attached to the femur and to the tibia and is responsible for holding the knee joint together in the Coronal plane on the medial side of the leg).